.NET Core Push Notifications for Web, Android and iOS
Send notifications to:
✅ iOS - Apple Push Notifications (APN)
✅ Android - via Firebase Cloud Messaging (FCM)
✅ Web - via Firebase Cloud Messaging (FCM)
CorePush is a simple lightweight library with minimal overhead. Send notifications to Android and Web using Firebase Cloud Messaging and iOS APN with JWT HTTP/2 API.
Installation
NuGet Package
Version 4.0.0+ requires .NET7.0. For earlier versions please use v3.1.1 of the library as it's targeting netstandard2.0, though please note, it uses legacy FCM send API.
The easiest way to get started with CorePush is to use nuget package.
dotnet cli:
dotnet add package CorePush
Package Manager Console:
Install-Package CorePush
Firebase Cloud Messages for Android, iOS and Web
To start sending Firebase messages you need to have Google Project ID and JWT Bearer token. Steps to generate JWT bearer token:
Create Service Account with "Firebase Service Management Service Agent" role.
Download Service Account JSON file and use it to configure FirebaseSender.
Sending messages is very simple so long as you know the format:
var firebaseSettingsJson = await File.ReadAllTextAsync('./link/to/my-project-123345-e12345.json');
var fcm = new FirebaseSender(firebaseSettingsJson, httpClient);
await fcm.SendAsync(payload);
{
"message":{
"token":"bk3RNwTe3H0:CI2k_HHwgIpoDKCIZvvD this is DEVICE_TOKEN",
"notification":{
"title":"Match update",
"body":"Arsenal goal in added time, score is now 3-0"
},
"android":{
"ttl":"86400s",
"notification"{
"click_action":"OPEN_ACTIVITY_1"
}
},
"apns": {
"headers": {
"apns-priority": "5",
},
"payload": {
"aps": {
"category": "NEW_MESSAGE_CATEGORY"
}
}
},
"webpush":{
"headers":{
"TTL":"86400"
}
}
}
}
Apple Push Notifications
To send notifications to Apple devices you have to create a publisher profile and pass settings object with necessary parameters to ApnSender constructor. Apn Sender will create and sign JWT token and attach it to every request to Apple servers:
P8 private key - p8 certificate generated in itunes. Just 1 line string without spaces, ----- or line breaks.
Private key id - 10 digit p8 certificate id. Usually a part of a downloadable certificate filename e.g. AuthKey_IDOFYOURCR.p8
Team id - Apple 10 digit team id from itunes
App bundle identifier - App slug / bundle name e.g.com.mycompany.myapp
Server type - Development or Production APN server
var apn = new ApnSender(settings, httpClient);
await apn.SendAsync(notification, deviceToken);
IMPORTANT: Initialize 1 ApnSender per bundle. When you send many messages at once make sure to retry the sending in case of an error. If error happens it's recommended to retry the call after 1 second delay (await Task.Delay(1000)). Apple typically doesn't like to receive too many messages and will ocasionally respond with HTTP 429. From my experiance it happens once per 1000 requests.
You can find expected notification formats for different types of notifications in the documentation. To make it easier to get started, here is a simple example of visible notification (the one that you'll see in phone's notification center) for iOS:
public class AppleNotification
{
public class ApsPayload
{
[JsonProperty("alert")]
public string AlertBody { get; set; }
}
// Your custom properties as needed
[JsonProperty("aps")]
public ApsPayload Aps { get; set; }
}
Use [JsonProperty("alert-type")] attribute to serialize C# properties into JSON properties with dashes.
Setup for ASP.NET Core with Dependency Injection
Both ApnSender and FirebaseSender have dependencies that need to be registered in order to enable DI.
Register HttpClient in Startup.cs. This will allow injection of HttpClient into the FCM and APN senders:
If you've added ApnSettings and FirebaseSettings into a configuration section, you can bind section directly to settings object from IConfiguration available in Startup.cs:
var section = configuration.GetSection("ApnSettings");
var settings = new AppSettings();
section.Bind(settings);
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
